The answer is x ≤ 6
Explanation/steps:
1) Our goal is to isolate x by moving all the numbers on its side to the other side. To get rid of -10, we add 10 to both sides, because whatever you do to one side you must do to the other
5x - 10 + 10 ≤ 20 + 10
5x ≤ 30
2) Now, we want one x instead of 5, so we divide both sides by 5
5x/5 ≤ 30/5
x ≤ 6
